fix a bug for respose ibtp update index

plugin/dapp/broker/executor/brokerdb.go

@@ -109,11 +109,11 @@ func (b *BrokerDB) updateIndex(payload *brokertypes.UpdateIndex) (*types.Receipt
 		if err != nil {
 			return nil, fmt.Errorf("broker not init!")
 		}
-		idx := meta.Meta[genServicePair(payload.SrcServiceID, payload.DstServiceID)]
+		idx := meta.Meta[genServicePair(payload.DstServiceID,payload.SrcServiceID)]
 		if payload.SequenceNum != idx+1 {
 			return nil, fmt.Errorf("incorrect index, expect %d", idx+1)
 		}
-		meta.Meta[genServicePair(payload.SrcServiceID, payload.DstServiceID)] = idx + 1
+		meta.Meta[genServicePair(payload.DstServiceID,payload.SrcServiceID)] = idx + 1
 		kvset := b.GetMetaKVSet(payload.ReqType, meta)
 		// 跨出交易不需要确认是否成功
 		receipt.KV = append(receipt.KV, kvset...)